Multiple service tap



w. P. HERMAN MULTIPLE SERVICE TAP Aug. 6, 1940.

3 Sheets-Sheet 1 Filed Oct. 17, 1938 Aug. 1940- w. P. HERMAN 2,210,215

' MULTIPLE SERVICE TAP Filed 001:. 17, 1938 3 Sheets-SheetB INVENTOR BY W n;

ATTORNEY Patented Aug. 6,

UNITED- STATES PATENT "OFFICE 2,210,215 MULTIPLE snavrcnmr William 1?. Herman, Providence, R. I. Application October 11, 1938, Serial No. 235,336

I tolai s. (01.173-334) My present invention relates to electrical multiple service tap, devices, and has particular reference to a novelrconstruction and a novel method of assembly ot the parts thereof. It is the principal object of my invention to provide a multiple'service tap having an integral, one-piece, resilient body.

It is an additional cbjectof my invention to provide a multiple service tap in which the contact prongs may be assembled without use of screws or similar anchoring means.

It is a further object of my invention to provide a novel method of assembly for mounting the contact prongs in the multiple tap, and anchoring the contact prongs within the tap. It is a further object of my invention to provide a service tap having the cord lead wire effectively anchored to the contact prongs so as to withstand sudden pulls or jerks and to provide strain relief.

Another object of my invention is to provide a multiple servicetap inwhich the body of the tap is shaped to eliminate the danger of short circuiting'and arcing.

Still another object of my invention is to provide a tap which utilizes resilience of the tap body to ensure the desired contacting engage-. ment of the cooperating prongs, and to secure the contacts within their slots.

With the above and other advantageous features in view, my invention consists of a novel method of assembly and a novel arrangement of of the form shown in Fig. 14;.

1 of the tap fixed to a length of cord lead wire so parts more fully disclosed in the detailed description following, in conjunction with the accompanying drawings, and more particularly defined in the claims appended hereto.

In the drawings: Fig. l is a front elevation of a multiple service tap employing my invention;

Fig. 2 is a side elevation oi thesame; Fig. 3 is a bottom view of the se; i Fig. 4 is an enlarged section taken along line fl4 of Fig. 1; r Fig. 5 is an enlarged line 5-5 of Fig.1;

the

of the same;

section 2 taken along the Fig. 6 is an enlargedsection taken along the.

Fig. 9 is an enlarged edge view of the other conanother form Fig. '16 is a perspective view of resilient rubber, in any suitable manner, but pref erably as described in my copnding application,

Fig. 11 is an enlarged plan view of a modified form of contactprong/in assembled position;

of contact prong in assembled position;

Fig. 15 is a perspective view of one of the blades the other blades;

and

Fig. 17 is an enlarged sectional view, similar to Fig. 6, of a modified form of service tap.

Multiple service"taps are conventionally designed to provide three additional places forinsetting electrical contact plugs. The conventional 'tapsare designed in various forms, one form for example having three contact portions 80 that'an extension plug is provided which can be pluggedinto the wall and provides three outlets adjacent any electrical equipment, another form having a, tap provided with prongs to'be plugged into a wall outlet and thus provide three outlets in place of the single wall outlet; threeis also a combination of the two in which two outlets and a length oi cord are plugged into a wall receptacle.

The form illustrated in Figs. 1 to 6 inclusive or thegdrawings illustrates applicant's. embodi-,

ment of the triple outlet, electrical cord connection type, Fig. 17 showing thecontact bladesdisplacing the cord lead wire, and Figs. 11 to 16 inclusive illustrating various forms of contact prongs which can be used with any type of tap.

Fig. 101; illustrates a preferred type of prong to" be used with the combination form above referred to. l

, Referring to the extension cord form illustrated in Figs, 1 to 6 inclusive, the body portion 26 of the multiple service tap may be of any suitable material, but is preferably molded in one piece of Serial No. 90,042,entitled Mold constructions for contact plugs, filed July 11, 1936.-

The body portion 20 comprises a conical upper portion 2| which receives the electrical cord connection 22, and has three outlet portions disposed in the same plane, outlet 23 opposite to conicalportion 2| and outlets 24 and 25 oppositely disposed at right angles thereto. 'The electrlcal cord connection 22 may be of any desired lenaiih and may have a conventional contact plug at its other end (notshown) for insertion into a wall receptacle. The conical cord receiving portion 2| terminates in an opening 26 which is approximately the diameter of the electrical cord lead wire '22, and is preferably slightly smaller so that a gripping action is obtained on the cord lead wire to relieve the strain on the cord lead wire connection to the contact prongs. The electrical cord connection extends into a cord receiving chamber 21-:which diverges into two slots 28 and 29, the resilient rubber body extending between the diverging portions of said slots to form a dielectric baflle 30. The upper ends of the slots 28 and 29 at'the base of the baflie 30 are provided with spaced parallel integral projecting portions 3| and 32 having shoulders, which form a restricted passageway portion therebetween (see Fig. 6).- Referring to Fig. 4, slots 28 and. 29 extend through the plug body, the ends of said slots having shoulders 33 and restricted slot portions 34 forming exit landings.

Extending transversely through the service taps in spaced parallel relation, are slots 35 and 36 terminating in the portions 24 and25 of the tap body. ,These slots are so positioned that the central portions thereof cross slots 28, and 29 at right angles to form slightly enlarged slot areas 31 and 38 (see Fig. 4). Slots 35 and 36 are of similar widths to slots 28 and 29 and terminate in'restricted slot exit portions 39 and. 48 with shoulders 4| and 42 at each end thereof. Each of the intersections of slots 28 and 29 with the slots 35 and 36 is provided with integral, outwardly extending baflie portions 43 and 44 which form restricted combined slot passageway por-' sive, the contact prong 41 comprises a longitudinal blank of electrically conductive metal, having each end thereof bent upon itself, as in Fig. '7, to

form wing portions 48 and 49. Each side edge of the blade 41 is provided with spaced, parallel, inwardly extending, oppositely disposed cut-out portions 50 and with shoulders. The main body portion, at each side of the-shoulder.portions 58 and 5|, is provided with oppositely disposed struck-up lugs 52 and 53, and the ends of the wing portions 48 and 49 are also preferably provided with detents 54 for better frictional electrical contact. These. contact prongs are adapted to set into the slots 35 and 36. v

.The .prongs which set into the slots 28.and 29 are the prongs to which the cord lead wires are attached. Each prong 55 (see Figs. 9 and comprises a rectangular, electrically conductive 'blank having one end thereof bent back uponitself to form a double thickness as at 56 and the other end bent back to form a wing portion 51.

The center of the blank .is provided with-a struckup lug 58, and the end having the wing portion has an opening forass'embly purposes. The poretion 56 is provided witha transverse slot 59, ad-

, jacent the end, and an angularly disposed slot 68 adjacent thereto. Between the struck-up lug 58 and slots 59 and 68 are oppositely disposed,

spaced parallel cut-out portions 6| and 62 with abrupt shoulders. i c

While, any method of assembly of the prongs and tap bqdycan be used, I prefer to use the apparatus disclosed in my copending application,

matured into Patent No. 2,198,966, issued April Referring to Fig. 6, the end of the electrical cord connection is firststripped of insulation and soldered or spot-welded to the upper edge of the blade as shown at 53. through the slot 59, over and through the slot 60, back past theslot 59, and out into the cord lead' connection. With this construction, the two slots and turns will provide a very powerful and strong anchoring means between the contact prong and the cord lead wire so that strong jerks or pulls cannot dislodge the electrical contact. Moreover, the angle at. which the slot 60 is disposed is such. that pulling on the cord lead wire locks it in the slot. 5 l

In assembling, the contact prongsJI are first pushed into their slots 35 and 36, either by hand or by machine. When the prongs-enter the slots,

' the first wing portion is bent inwardly by the abutments 43 and 44 until the contact prongs the prongs between the wing portions 48 and 49 and keep the prongs between theshoulders 4| and 42. The conical portion 2| of the tap body The cord is then pulled is then stretched'or distended, preferably by a machine of'the type disclosed in my copending application, hereinbefore referred to, the pull arms of the machine passing through slots 28 and 29 to hook into the openings in ,the wing portions of the blades 55. The withdrawal of the puil arms pulls each blade into its respective slot 28 and 29 into the position shown in Fig. 6. In this position, the cut-out portions 6| and 62. interlock with the abutments 3| and 32- in the tap body to anchorthe prongs in the body. The prongs cross and contact each other in-the .por-

tions 45 and 46,as shown in Fig.5, and the abut-- ments 43 and retain the cord connected prong 55 in contact with the blade 41.

To -further eflectively anchor the blade, the struck-up lugs 58 snap into the cuteout portions 58 (or 5| on the opposite blade which is turned into the conical portion 2| of the tap body and are pressed into their respective positions so that they cannot be dislodged by' hard use of the service tap. v

If desired, the prong a,shown in Flg.'10a, can be used instead of the prong 55 so that the service tap may be provided with contact prongs at a point opposite thecord lead connection, for insertion into a wall receptacle. The prong 55a is shown in the solid form to be us'edin conjunction with the prong shown in Fig. 16 hereinafter to be describedfhowever, the form shown in Fig. 10, prong 55, 'can be used, modified as in Fig. 10a.

Instead of the prongs 41 and 55, the prong shown in Figs. 11 to. 13 inclusive may be used. Referring to Fig. 12, the prong 64 is similar to the prong 55 except that the lug 58 is eliminated and the wing portion 51 is flattened against the prong to form a double thickness of prong-with an intermediate, single thickness 65. with this type of prong, I prefer to use the short cross prong 66 shown in Fig. 13, this crossprong being similar to prong 41 except that there are no outout portions and no struck-up lugs, the wing portions 48 and 49 being flattened. against the prong but held slightly away from the body of the prong by detents 61. In using this form, the assembly thereof is as shown in Fig. 11, the central one-thickness cut-,out portion 65 in blade 64, and portion 68 in blade 66, interlocking to lock the prongs together in their positions in the tap body. The balance of the tap body, including the cut-out shoulder portions, etc., heretofore described is the same, and the method of assembly is similar. I

If desired, the prongsmay be of solid construction as shown in Figs. 14 to 16 inclusive. In this construction the longer prong ,69 is slotted in the upper portion similarly to the prongs 64 and 65',

20 but has a smooth, straight body'portion with an extruded opening 10 in the center thereof, formed b3 punching the opening with a conical die and forcing the edges of the opening upwardly. The

. short cross prong II is offset inits center to form portion I2 and is. provided'with an opening 13 slightly larger, than the circumference of the extruded opening 10. In this. construction, assembled as shown in Fig. '14, the indented portion 12 snaps over the edge of the prong 69 and the opening I3 snaps over the extruded portion of the opening III to prevent the disengagement of the prongs and to provide an effective lock.

Instead of the tap body used in Fig.6, the body shown in Fig. 17. may be used. This haslfour .35" outlet points which are disposed at right angles to each other, the longer prong ll being provided with protruding contact portions instead of the cable attachment shown in Fig.- 6. In this form, the tap ismerely plugged into a wall receptacle 6 to provide a plurality of outlets. The form shown in Fig. 17 illustrates the use of a solid bladeas shown in Figs. 14 to 16. inclusive. Howthe dielectric restricted slot portions. Any small almost made direct contact with the service tap blade, thus reducing the arcing to a minimum. Similarly, in withdrawing the plug, the arcing frame is almost immediately snuffed by quirements for different tap,designs, without 'de-.

parting from the spirit and the scope of the invention as defined in the appended claims.

I claim:

1. Ina multiple service tap, a one-piece body of moldedsoft resilient material having a plurality of angularly related intercommunicating contact receiving slots extending inwardly from the surfaces thereof, contacts mounted within. 25 said slots in electrical and mechanical interlocking engagement with each other, said body constituting yielding resilient means for retaini said contacts within said slots.

In a multiple service tap, a one-piece body of molded soft resilient material having a plu-- -rality of pairs of angularly-related intercommuni cating contact, receiving slots extending inwardly from the surfaces thereof, pairs'of contacts mounted within'said slots, one contact of each pair being in electrical and mechanical interlocking engagement with one contact of another pair, saidbod'y constituting yielding resilient'meansfor retaining said'contactswithinsaid slots.

ever, any type or form of blade may be used interchangeably. with any of the forms herein described or aify other standard type of blade notshown. 1

The use of the aoove described method of manufacture, and assembly. provides a multiple service tap with an integral, one-piece body of 5 resilient material, which is easy and economical to manufacture and assemble, the cord lead being very firmly anchored to'the contact blade to eliminate danger of shortcircuiting and arcing,

the tap being readily adapted for different types of multiple service taps s h as the-forms shown oreover, the use of a" contacting and holding pressure on the contact-.

ing .surface of the service pl rongs."

When the service plug prongs 'are pushed into or pulled out of a conventional multiple service. o5 tap, arcing takes place before contact isgmade and -after the contact is broken. Also, when the plug becomes loosened and contact is partially'broken,

, a continuous arcing resultsf This arcing will burn out the tap, and sometimes causes fires,

5'70 electrical shocks and burns. flBy r t tm' th slot exits, as at'34, 39 and 40, this arcingis sub-' stantially eliminat'edi. As the plug blade is pushed into the slot, the restricted portion sur- ,rounds and encases the blade in the rubber and prevents arcing until the tip of. the blade has 3. In a multiple service tap, a one-piece bodyof molded softresilient material having a plurality of pairs of right-an'gularlyrelated intercoinmunicating contact receiving slots extending inwardly from the surfaces thereof, pairs of contacts mounted within said slots, one contact of each pair being in electrical and mechanical interlocking engagement with one contact of another-pair, said body constituting yielding resil- 5o ient means for retaining said contacts within said slots.

4. In a multiple service tap, a tine-piecebody of molded soft resilient material having a plurality of pairs of right ang ularly related inter- 55 communicating contact receiving slots extending inwardly from the surfaces thereof and through 'saidbody, pairs of contacts mounted within said slots, one contact of each pair. being in electrical and mechanicalinterlocking engagement with one contact. of another pair, said body constiof molded soft resilient material having a plug ,ralityjof pairs of right angularlyrelated inter- "communicating contact receiving slotsextending inwardly fromthe surfaces thereof and through .said body,p'airs of contacts mountedwithin said slots,-one contact ofeach pair'being in electrical 6 and mechanical interlocking" engagement with one contact of another pair, 'said body constituting yielding resilient'means for retaining said contacts within said slo one pair of contacts extending. beyond said dy to provide means Q contacts mounted within said slots, one contact of each pair being in electrical and mechanical interlocking engagement with one contact of'another pair, said body constituting yielding resilient means for retaining said contacts within said slots, one of each pair of slots being formedto join to provide a cord receiving passage within said body, and a pair of electrical conducting wires extending into said passageway in electrical conducting engagement with one pair of said 0on tacts.

'7. In a multiple service tap, a one-piece body of molded soft resilient material having a plurality of angularly related intercommunicatlng contact receiving slots extending inwardly from the surfaces thereof, contacts mounted within said slots in electrical and mechanical interlocking engagement with each other, said body constituting yielding resilient means at the intersection of said slots for retaining said contacts within said slots.

8. In a multiple service tap, a one-piece body of molded'soft resilient material having a plurality of angularly related intercommunicating contact receiving slots extending inwardly from the surfaces thereof, contacts mounted within said slots in electrical and mechanical interlocking engagement with each other, said body constituting yielding resilient means for retaining said contacts within'said slots, at least one of said slots being of greater length than the contact therein whereby a flexible slot mouth beyond the end of said contact is provided.

WILLIAM P, HERMAN. 

